Exploration of a novel three-dimensional knitted spacer air filter with low pressure drop on cooking fume particles removal

Abstract Cooking fumes, which are harmful to the environment and to human health, have become a main source of air pollution in cities. At present, fibrous materials, such as glass fiber filters, are widely used to filtrate cooking fumes, but such materials remain challenged by the face-loading of cooking fumes and rapid increases in pressure drop that result in substantial energy consumption from gas transport in ventilation systems. In this study, the potential use of a novel three-dimensional knitted spacer air filter (3D filter) for fume particle removal, which can overcome these challenges, was experimentally investigated. Dynamic filtration measurements were performed in experimental conditions that were as representative as possible of oil aerosol, with Di-Ethyl-Hexyl-Sebacate (DEHS) particles ranging in size from 1.0 to 4.0 μm. The results showed that the 3D filter exhibited a high filtration efficiency (90% for 3.0-μm particles) and a low pressure drop that was less than 52 Pa at an air velocity of 2.5 m/s. The air cleaning capability of the 3D filter for cooking fume aerosols generated by edible oils was also studied. The arrestance of the 3D filter for cooking fumes was 84.0% at an air velocity of 2.5 m/s, and the relative oil treatment capacity was four times that of a nonwoven filter with the same thickness. Comprehensively considering filtration efficiency, pressure drop, and oil treatment capacity, the 3D filter was demonstrated to be a competitive pre-filter for cooking fume removal in cooking ventilation systems.